Why can't Christians Verify Exactly Where Jesus Was Buried?

[Thumpalumpacus]

You cannot reformulate the Sermon on the Mount from James, it is substantially different and includes other areas of Jesus's teachings that are consistent with but not included in that sermon. What's most important of all is that almost nothing in James is found in the gospel of Mark at all.

Wait, you went from Matthew to Mark here.

It is exclusively from a separate account of Jesus's teachings (that is we have Mark as one source, and another source whether Q or James himself or an oral tradition for James). In addition to the Sermon on the Mount we have yet another sermon (Sermon on the Plain) which is substantially similar, but not the same, to it found in Luke.

And now to Luke?

Now they could be the same sermon that has been recorded in two different ways, or they could be Jesus delivering the same or similar sermons on different occasions (which is the more likely because we would expect a preacher to give different audiences the same messages at different times).

That's kinda my point. It's not like they had tape recorders back then, and it's not like any putative authors had recordings to work from. So the idea that they could work with notes from one, or several, iterations of the same essential speech, seems pretty understandable to me.

Again, using James as a source would not give the sermon on the mount because nowhere does James inform the audience that he is directly quoting Jesus.

So what? He could simply be promulgating ideas he found nice enough without crediting the speaker, and even so Matthew, from other sources, could have found verbiage similar enough to regard James as useful, too -- corroboration in his own mind.

Your underlying assumption seems to be perfect knowledge on the part of the authors of the Gospels, and that seems pretty questionable, to me.